Supplement Abstract This application is being submitted in response to NOT-MD-19-023. Research examining prevalence of dental caries in children has found higher prevalence among low-income children, but for some racial/ethnic groups there are additional disparities even when income and insurance status has been controlled for. This intersection has not been explored within the Native Hawaiian / Other Pacific Islander (NH/OPI) pediatric population. Our long-term goal is to reduce disparities in children?s oral health, largely by improving dental care quality through evidence-based prevention and treatment. Understanding the dental care system?s role in creating or mitigating oral health disparities or improving oral health has been limited to simplistic access metrics (e.g., annual dental visit) and procedures billed (e.g., dental treatment) which only allow general comparisons heavily confounded by quality of care and insurance type. We know little about how caries risk status, diagnoses, preventive therapies, and interventions are linked to oral health in specific individuals and in populations over time. This gap in knowledge can now be overcome through our study of a caries prevention program. The program is built into a system that includes a standardized model of diagnosis-driven, risk- based, clinical-decision-supported care documented in an electronic health record (EHR) and implemented at a dental accountable care organization serving both commercially insured and Medicaid patients. The proposed study supplement will enable novel assessment detailed disease patterns and health disparities of Native Hawaiian/Other Pacific Islander (NH/OPI) children through additional in-depth analysis. This study will leverage sophisticated dental informatics allowing us to use big data to measure and comparatively examine untreated caries and new caries incidence over time in the context of real-world clinical care. Additionally, using Oregon Medicaid claims data we can assess the delivery system impact and by conducting focus groups we will identify impactful patient centered care considerations that can potentially predict the success of intervention ? all critical information to inform future quality improvement and implementation efforts.